1. Field of the Invention
The present invention relates to an electric operator for a molded case circuit breaker, switches and the like and, more particularly, to an electric operator having a reciprocally mounted actuator, adapted to be mechanically coupled to a circuit breaker operating handle, for moving the operating handle between an open position or, alternatively, to a closed position, which includes an electric motor for driving the actuator and allowing the circuit breaker to be controlled from a remote location and a mechanical crank assembly which alternatively allows for manual operation of the actuator in the event of a loss of electric power to the electric motor.
2. Description of the Prior Art
Molded case circuit breakers are generally used to provide overcurrent protection for various types of electrical equipment. However, in some applications, it is necessary to control such circuit breakers from a remote location. Also molded case switches are known. In such applications, electric operators may be provided that are adapted to be mechanically coupled to the operating handle of the circuit breaker or molded case switch. Both solenoid operators and motor operators are known. Examples of solenoid operators for molded case circuit breakers and switches are disclosed in U.S. Pat. Nos. 4,553,115 and 4,642,726, assigned to the same assignee as the present invention. However, such solenoid operators are generally slow acting. Motor operators, on the other hand, are generally provided with high speed electric motors that are comparatively faster acting than a solenoid operator. An example of a motor operator is disclosed in U.S. Pat. No. 4,990,873, assigned to the same assignee as the present invention.
Both solenoid operators and motor operators are adapted to be rigidly mounted relative to the circuit breaker or molded case switch to be in communication with the operating handle. Such operators may either be disposed within the circuit breaker or switch housing or mounted either on the side or in the front of the circuit breaker. U.S. Pat. Nos. 4,553,115 and 4,642,726 breaker housing. U.S. Pat. No. 4,990,873 disclose motor operator mounted to one side of the circuit breaker housing.
Irrespective of the mounting arrangement of the electric operator relative to the circuit breaker or switch, the electric operator must include means for manual operation. This requirement for manual operation, promulgated in Underwriter's Laboratories Standard No. UL 489, is to allow for manual operation of the circuit breaker in the event of loss of electric power to the electric operator.